Oral Mucocele

An oral mucocele is a harmless mucus-filled cyst on the inside of your mouth. The cysts are usually painless and look like smooth, round lesions. Trauma such as biting your lip cause most oral mucoceles. You typically don’t need treatment because the cyst should go away by itself. Your provider can remove large cysts or ones that cause discomfort.


What is an oral mucocele?

An oral mucocele is a painless fluid-filled cyst on the inner surface of your mouth. Also known as a mucous cyst, these harmless blisters appear most often on the inner part of your lower lip. They can also affect your inner cheeks, tongue, gums and the floor of your mouth.

Oral mucoceles, or mucous cysts, usually occur due to minor trauma, such as biting your lip. When you sustain an oral injury, you may damage or block a salivary gland. When this happens, the flow of saliva draining into your mouth from that gland may build up and form a cyst.

Oral mucoceles normally go away on their own. But large cysts can cause issues with talking, chewing, swallowing and in rare cases, breathing. Therefore, you should see your healthcare provider to have them remove any large oral mucoceles.


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Who do oral mucoceles affect?

Oral mucoceles most often affect people younger than 30 years old, but they can affect people of any age. People between the ages of 3 and 20 years old make up 70% of cases. The peak age of occurrence is between the ages of 10 and 20 years old.

How common are oral mucoceles?

In the general population, oral mucoceles occur in 2.4 out of every 1,000 people.


Symptoms and Causes

What are the symptoms of an oral mucocele?

An oral mucocele will look like a soft, dome-shaped lesion in your mouth. They’re usually clear or have a bluish tone, and they vary in size from 1 millimeter to 2 centimeters wide.

Oral mucoceles most commonly affect the inner surface of your lower lip. But they can also occur on your inner cheeks, tongue, gums and the floor of your mouth. An oral mucocele on the floor of your mouth is called a ranula. Oral mucoceles don’t usually cause any pain, but large cysts may cause discomfort if they interfere with your speech, chewing or swallowing.

What causes an oral mucocele?

Oral mucoceles generally occur due to trauma to your salivary glands or a salivary gland opening (duct) blockage. When you endure an injury to your salivary glands, there’s a disruption in the flow of saliva. The saliva can build up and form a cyst.

One of the most common causes of trauma is biting your lip while you’re chewing. Other oral mucocele causes include:

  • A lip-biting or lip-sucking habit.
  • Long-term (chronic) inflammation due to smoking or using tobacco products.
  • Thickened or damaged salivary ducts.
  • Trauma from intubation.

Diagnosis and Tests

How is an oral mucocele diagnosed?

Your healthcare provider will diagnose an oral mucocele based on your symptoms and a physical examination. While they can usually determine the condition by looking in your mouth, they may request further tests to confirm the diagnosis. These tests may include:

  • Ultrasound: An ultrasound uses high-frequency sound waves to create a real-time picture or video of your oral tissue.
  • Biopsy: During a biopsy, your healthcare provider removes some of the tissue from the cyst for examination.
  • Computed tomography (CT) scan: A CT scan is used in rare cases when a ranula has grown into your neck.

Management and Treatment

What is the treatment for an oral mucocele?

You may not need oral mucocele treatment because most lesions will rupture and go away by themselves. You shouldn’t attempt to get rid of an oral mucocele on your own. Oral mucocele home treatment can cause an infection or damage to your oral tissues.

For cysts that repeatedly come back or for large mucoceles, your healthcare provider may recommend the following treatment options:

  • Cryotherapy: Your healthcare provider will apply extreme cold to freeze and destroy the mucocele cyst.
  • Laser treatment: Your provider will use a special laser to remove the lesion.
  • Surgical excision: An oral surgeon or dentist will cut out and remove the cyst. They may also remove the salivary gland.

How long does it take to recover from oral mucocele treatment?

Recovery time will depend on your type of treatment. Your healthcare provider may recommend a liquid or soft diet for a few days after cryotherapy or laser treatment. You may need to stick with a restricted diet for a longer period of time if you’ve had a surgical excision.

In addition, strenuous exercise is typically discouraged for the first few days or weeks, depending on the type of procedure.


How can I prevent oral mucoceles?

You may have accidentally bitten your lip or cheek while eating, and there’s no way to prevent that. But you can prevent oral mucoceles by kicking bad habits. Stop biting your lip and/or sucking on the inside of your cheeks. If you use tobacco, this is one more reason to quit.

Outlook / Prognosis

What is the outlook (prognosis) for an oral mucocele?

Oral mucoceles are normally harmless, painless cysts that don’t cause any long-term complications. The prognosis is generally good. But larger cysts may interfere with talking, chewing and swallowing. In rare cases, ranulas can cause difficulty breathing. With treatment, your healthcare provider can remove the mucocele and eliminate any possible issues.

Living With

When should I see my healthcare provider?

Most oral mucoceles will usually rupture and clear up on their own. But contact your healthcare provider if you have trouble talking, chewing or swallowing due to a large cyst.

A note from Cleveland Clinic

We’ve all done it — you’re chewing fast, not paying attention and then crunch — you’ve bitten the inside of your mouth instead of your food. Ouch! Accidentally biting your lip, tongue or cheek is one of the most common causes of oral mucoceles. Fortunately, these harmless cysts usually clear up and go away by themselves. If you notice a cyst that doesn’t seem to go away, or if a cyst is causing trouble with your speech, chewing or swallowing, call your healthcare provider. They can help diagnose and treat an oral mucocele if necessary.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 07/01/2022.

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